Improvement in stop-valves



R. THOMAS. Stop-Valve.

' No. 208,214. .Patentefld sept. 17. 1878.

PETERS. FHOTO-LITHOGRAPHER, WASHINGTO D C UNITED STATES PATENT OFFICE.

RICHARD J. THOMAS, OF MILWAUKEE, WISCONSIN.

' IMPROVEMENT IN STOP-VALVES.

Specification forming part of Letters Patent No. 208,214, datedSeptember 17, 1878; application filed February 21, 1878.

To all whom it may concern:

Be it known that I, RICHARD J. THOMAS, of Milwaukee, in the county ofMilwaukee, in the State of WVisconsin, have invented certainImprovements in Stop-Valves, of which the following is a specification:

My invention has for its object the stopping of steam from passingthrough a pipe. It is a valve constructed with two seats opposite eachother, and two gates with a roller between them, which, working againstan incline on one of the gates, forces them apart and against the seats.

Referring to the drawing forming part of this specification, Figure l isa sectional view of my invention, showing the gates across theircenters; and Fig. 2, a sectional view of the same in reverse.

In the drawing, A A are the two valveseats; B, a straight gate; 0, agate with an incline across its center, thicker at the bottom of thegate and thinner at its top; I), a roller on the straight gate, whichpresses against the incline on the gate G, and thus, as the straightgate goes down, presses the two gates against thetwo seats A A. E isaslotinthe top of the gate with the incline on it. F is a slot in thetop of the straight gate, narrower than the slot in the other gate; G, aspring round the top of the gates and the stem H, which holds themtogether, the stem H having a head on its lower end, which enters theslots in the two gates; I, the upper part of the shell of the valve.

This valve is operated as follows: When the valve is closed, to open thesame, turn the stem H, and the screw on the same will raise it, and thehead on the same, pressing against the top of the slot in the gate B,will raise the same, while the wide slot in gate 0 will allow gate 0 toremain closed till the roller, rolling on the incline, will loosen thetwo gates, and then the head on the stemH will strike against the upperside of the slot in gate 0, when the two gates will be raised together.To close the valve, reverse the motion of stem H, and the two gates willbe closed. The straight gate, lagging behind a little, will, when thegate with the incline on it strikes the bottom,

move on, and the roller, rolling against the incline, press the twogates tight against the two seats. The seats are made parallel to eachother, so that, when needingrepairs, they can be turned ott true withouttrouble. The spring G is to hold the tops of the gates together, andalso to press on the gate 0, so that it shall reach its seat first.

What I claim as new, and desire to secure by Letters Patent, is

1. Gates B and O, with slot E made deeper in the inclining gate thanslot Fin the straight gate, roller D, spring G, and valve-seats A A, incombination with stem H, substantially as described.

2. Spring G, in combination with gates B and O, with slot E in theinclining gate made deeper than slot F in the straight gate, and rollerD, substantially as specified.

- RICHARD J. THOMAS.

Witnesses:

' J. B. SMITH,

E. SHAW.

